Laryngeal Langerhans Cell Histiocytosis: A Case Report and Literature Review.

OBJECTIVE: To describe a case of laryngeal Langerhans cell histiocytosis, discuss its characteristic features and management, and provide a review of the available literature. METHODS: A patient presenting to a tertiary care medical center with dyspnea and hoarseness is described. A literature review of laryngeal Langerhans cell histiocytosis cases was performed through a search of articles indexed in the National Institutes of Health PubMed system. RESULTS: We report a case of a 69-year old male, who presented with a laryngeal mass highly suspicious for laryngeal squamous cell carcinoma, was treated with laser excision, and was subsequently found to have laryngeal Langerhans cell histiocytosis upon histological analysis. Including our current case, we found six prior reported cases of laryngeal Langerhans cell histiocytosis in the literature. Of the six cases, four were in adults, while two were in children. Dyspnea is a common presenting complaint present in all cases. Smoking may be a potential risk factor. CONCLUSIONS: Laryngeal Langerhans cell histiocytosis is a rare condition and an important consideration in the differential diagnosis of patients presenting with a laryngeal mass and symptoms of dyspnea or hoarseness. Biopsy and histopathological analysis are key to the diagnosis. Surgical excision and radiotherapy are successful treatments used in clinical practice.

Histiocytic disorders: insights into novel biology and implications for therapy of Langerhans cell histiocytosis and Erdheim-Chester disease.

Langerhans cell histiocytosis (LCH) and Erdheim-Chester disease (ECD) are caused by mutations of the MAPK pathway, most often BRAFV600E, in myeloid dendritic cells that lead to some overlapping and other unique presentations of the two diseases. LCH occurs in both children and adults, but ECD is primarily found in the latter. The challenges in diagnosing these conditions relates to the rarity of the conditions and that they mimic diseases that are more widely understood, such as certain rashes; bone, lung, and renal diseases; and other malignancies. The histopathology of LCH is definitive, but not so for ECD. Treatment with BRAF and MEK inhibitors has become one of the important advances in the care of these patients.

Mechanisms of Exercise Limitation and Prevalence of Pulmonary Hypertension in Pulmonary Langerhans Cell Histiocytosis.

BACKGROUND: Pulmonary Langerhans cell histiocytosis (PLCH) determines reduced exercise capacity. The speculated mechanisms of exercise impairment in PLCH are ventilatory and cardiocirculatory limitations, including pulmonary hypertension (PH). RESEARCH QUESTION: What are the mechanisms of exercise limitation, the exercise capacity, and the prevalence of dynamic hyperinflation (DH) and PH in PLCH? STUDY DESIGN AND METHODS: In a cross-sectional study, patients with PLCH underwent an incremental treadmill cardiopulmonary exercise test with an evaluation of DH, pulmonary function tests, and transthoracic echocardiography. Those patients with lung diffusing capacity for carbon monoxide (Dlco) < 40% predicted and/or transthoracic echocardiogram with tricuspid regurgitation velocity > 2.5 m/s and/or with indirect PH signs underwent right heart catheterization. RESULTS: Thirty-five patients were included (68% women; mean age, 47 ± 11 years). Ventilatory and cardiocirculatory limitations, impairment suggestive of PH, and impaired gas exchange occurred in 88%, 67%, 29%, and 88% of patients, respectively. The limitation was multifactorial in 71%, exercise capacity was reduced in 71%, and DH occurred in 68% of patients. FEV1 and Dlco were 64 ± 22% predicted and 56 ± 21% predicted. Reduction in Dlco, an obstructive pattern, and air trapping occurred in 80%, 77%, and 37% of patients. FEV1 and Dlco were good predictors of exercise capacity. The prevalence of PH was 41%, predominantly with a precapillary pattern, and mean pulmonary artery pressure correlated best with FEV1 and tricuspid regurgitation velocity. INTERPRETATION: PH is frequent and exercise impairment is common and multifactorial in PLCH. The most prevalent mechanisms are ventilatory, cardiocirculatory, and suggestive of PH limitations. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov; No.: NCT02665546; URL: www.clinicaltrials.gov.

Egyptian experience in Langerhans cells histiocytosis: frequent multisystem affection and reactivation rates.

Background: Histiocytoses are unique disorders; their clinical presentations vary from self-healing lesions to life-threatening disseminated disease. Objectives: We aimed to evaluate the different clinical presentations, frequency of reactivations, and treatment outcome of Langerhans cell histiocytosis among Egyptian children. Methods: we restrospectively analyzed the data of 37 Langerhans cell histiocytosis patients (LCH) registered at Ain Shams University Children's Hospital for clinicopathological features, treatment modalities and their outcomes. Results: Twenty seven (73%) of the studied patients with LCH had multisystem disease (MS), 24 (88.9%) of them had risk organ involvement (MS RO+) and only 3 without risk organ (MS RO-). Most of the patients received LCH III protocols. Eleven patients (29.7%) had reactivations with median time till reactivation of 17 months (IQR 5-23).Reactivation rates were 40% and 50% in patients with no evidence of active disease (NAD) and those with active disease better (AD better) at week 6 evaluation respectively (p = 0.71).We report 9 deaths (all had MS RO+, two died after reactivation and 7 had progressive disease. The 5 years EFS and OS were 49.4% and 81.2% respectively. Risk stratification did not significantly affect the EFS or OS (p = 0.64 and p = 0.5 respectively). Conclusion: A high reactivation rate was encountered in children with LCH and MS-RO + irrespective of 6 weeks response to induction therapy. A high mortality in patients with progressive disease necessitates a possible earlier aggressive salvage in such group.

Pulmonary Langerhans cell histiocytosis in cats and a literature review of feline histiocytic diseases.

OBJECTIVES: The aim of this study was to report the clinical, radiographic and pathological features of pulmonary Langerhans cell histiocytosis in four cats, and carry out a literature review of feline histiocytic diseases. METHODS: Necropsy reports archived at the Department of Veterinary Pathology of the Federal University of Rio Grande do Sul were reviewed. The clinical information was then obtained from the clinical records at the Veterinary Hospital. Routine samples had been collected during necropsy, fixed in 10% formalin, routinely processed for histology, and stained with hematoxylin and eosin. Samples of lung were submitted for bacterial and fungal culture. Tissue sections of lung underwent immunohistochemical testing for vimentin, pancytokeratin, CD18, CD3, CD79αcy, E-cadherin and Iba1. RESULTS: This disease affected mixed breed cats aged 7-14 years. Clinical signs consisted of severe mixed inspiratory and expiratory restrictive dyspnea, lethargy and anorexia. Thoracic radiographs revealed different lesion profiles, predominantly of an interstitial and alveolar pattern. Grossly, the lungs were diffusely firm and did not collapse. The pleural surface was bright and irregular due to multifocal-to-coalescent, well-demarcated, white, firm nodules that also extended into and obliterated the pulmonary parenchyma. Histological changes were characterized by poorly demarcated infiltration with histiocytic cells arranged in cohesive groups within the alveolar, bronchiolar and bronchial spaces. Histiocytic cells had intense cytoplasmic immunolabeling for vimentin and Iba1, and robust membrane immunolabeling with CD18 and E-cadherin; these cells were negative for CD3, CD79αcy and pancytokeratin in all cases. CONCLUSIONS AND RELEVANCE: This article confirms that pulmonary Langerhans cell histiocytosis is a rare disease that occurs in middle-aged to older cats and causes widespread involvement of the pulmonary parenchyma, inducing acute or chronic, progressive respiratory disease characterized by mixed restrictive dyspnea that eventually leads to death. While a definitive clinical diagnosis is challenging, the nodular appearance of the pulmonary changes, together with the histological and immunohistochemistry findings, suffice for diagnostic confirmation of pulmonary Langerhans cell histiocytosis.

Thoracic spine Langerhans cell histiocytosis in a child with achondroplasia.

Multifocal bone Langerhans cell histiocytosis (LCH) is usually treated with prednisolone and vinblastine. We present a case conservatively treated with indomethacin with good clinical and radiological response. A 7-year-old achondroplastic boy presented with worsening thoracic back pain and leg weakness. An admission MRI spine showed a pathological T1 vertebrae fracture with posterior soft tissue extension compressing and distorting the spinal cord. A CT guided biopsy revealed an LCH. Steroids were avoided to reduce osteopenia risk and further vertebral fragility. Considering the risk of a thoracic surgical approach in a child with this background, he was managed conservatively with indomethacin and a Sternal Occipital Mandibular Immobilizer (SOMI) Brace. Pain resolved completely within 6 months and the brace was discontinued. Serial follow-up scans showed progressive resolution of the pathological T1 fracture and complete resolution of the spinal cord compression.

Langerhans cell histiocytosis presenting as a rapidly evolving frontotemporal syndrome.

Langerhans cell histiocytosis (LCH) is a rare disorder in adults which usually manifests with involvement of multiple organ systems, including the central nervous system. We describe an unusual case of biopsy-proven LCH presenting with frontotemporal-dominant cognitive impairment with hypothalamic involvement, along with multisystem disease. We propose that the dementia was probably an immune-mediated process triggered by LCH which responded dramatically to high-dose steroids.

Central diabetes insipidus: beware of Langerhans cell histiocytosis!

Langerhans cell histiocytosis (LCH) is a rare disorder, characterised by a monoclonal proliferation of aberrant histiocytes that accumulate in and infiltrate into different organs. When the hypothalamic-pituitary axis is involved, central diabetes insipidus (CDI) can be its first manifestation. Three cases of LCH with central diabetes insipidus were retrospectively analyzed: Case 1 is a 41-year old female presenting with polyuria and polydipsia. Diabetes insipidus was diagnosed and treated with desmopressin. MRI pituitary showed hypophysitis. Subsequently, she developed bone lesions and a biopsy demonstrated LCH. Case 2 is a 51-year old female presenting in 2009 with polyuria and polydipsia. Diabetes insipidus was diagnosed and treated with desmopressin. MRI pituitary revealed hypophysitis. LCH was suspected because of known pulmonary histiocytosis. Coexisting bone lesions were biopsied and confirmed LCH. Case 3 is a 44-year old female presenting with diabetes insipidus. She was treated with desmopressin as well. MRI of the pituitary gland showed impressive thickening of the infundibulum. A few months later, she developed skin lesions and a biopsy revealed LCH. Conclusively, LCH is a rare, elusive and probably underdiagnosed disease with a broad disease spectrum. Due to infiltration of the hypothalamic-pituitary axis, CDI can be the first manifestation, even before LCH is diagnosed. Therefore, LCH should be considered in the diagnostic workup of CDI.

Histiocitosis de células de Langerhans con compromiso vertebral / Langerhans cell histiocytosis with vertebral involvement

Resumen: Introducción: La histiocitosis de células de Langerhans (HCL) es un trastorno histiocítico raro y su incidencia exacta se mantiene desconocida; se ha diagnosticado en todos los grupos de edad, pero es más común en los primeros 3 años de vida. Se caracteriza por lesiones únicas o múltiples de tipo osteolítico causadas por proliferación clonal de células histológicamente similares a las células de Langerhans; su presentación clínica es heterogénea. Caso clínico: Presentamos el caso de una paciente de sexo femenino de 7 años, con dificultad para la marcha y debilidad progresiva en los miembros inferiores de 5 días de evolución. A la exploración física presenta hallazgos concordantes con síndrome piramidal e hipoes­ tesias de miembros inferiores. Se realizó resonancia magnética (RM) de columna y tomografía computarizada de cráneo simple, que descartó patología intracraneal . En la RM de columna se detectó vertebra plana con extensión epidural y para­ vertebral, por lo que se inició manejo con esteroides y se indicó descompresión quirúrgica. Se realizó resección parcial y biopsia de la lesión. Debido a los hallazgos histológicos y la presencia de marcadores positivos para CD1a y CD207, se confirmó el diagnóstico de HCL. Conclusiones: La HCL es una enfermedad poco frecuente y de difícil diagnóstico por su presentación heterogénea. El granuloma eosinofílico y la vértebra plana como hallazgos imagenológicos pueden orientar el diagnóstico, aunque siempre se debe confirmar histológicamente.

Abstract: Background: Langerhans cell histiocytosis (LCH) is a rare disease, more common in the first three years of lite. lt is characterized by single ar multiple osteolytic lesions due to clonal proliferation of cells histologically similar to Langerhans cells; its clínical presentation is heterogeneous. Case report: 7-year-old female patient with 5 days of progressive lower extremity weakness and difficulty to walk. Physical exam findings were consistent with pyramidal syndrome and lower extremities hypoesthesia. Magnetic resonance imaging (MRI) of spine and cranial computed tomography (CT) were performed. lntracranial pathology was ruled out. The MRI findings showed vertebra plana with epidural and paravertebral involvement, so treatment with steroids and surgical decompression initiated. Partíal resection and biopsy of the lesion was performed. Due to histological findings and positive CD1a and CD207 markers, diagnosis of LCH was confirmed. Conclusions: LCH is an uncommon disease with a challenging diagnosis due to its heterogeneous clinical presentation. Eosinophilic granuloma and vertebra plana as imaging findings may guide the diagnosis. However, it should always be confirmed with histological evidence.

[Histiocitosis de células de Langerhans con compromiso vertebral]. / Langerhans cell histiocytosis with vertebral involvement.

Introducción: La histiocitosis de células de Langerhans (HCL) es un trastorno histiocítico raro y su incidencia exacta se mantiene desconocida; se ha diagnosticado en todos los grupos de edad, pero es más común en los primeros 3 años de vida. Se caracteriza por lesiones únicas o múltiples de tipo osteolítico causadas por proliferación clonal de células histológicamente similares a las células de Langerhans; su presentación clínica es heterogénea. Caso clínico: Presentamos el caso de una paciente de sexo femenino de 7 años, con dificultad para la marcha y debilidad progresiva en los miembros inferiores de 5 días de evolución. A la exploración física presenta hallazgos concordantes con síndrome piramidal e hipoestesias de miembros inferiores. Se realizó resonancia magnética (RM) de columna y tomografía computarizada de cráneo simple, que descartó patología intracraneal. En la RM de columna se detectó vertebra plana con extensión epidural y paravertebral, por lo que se inició manejo con esteroides y se indicó descompresión quirúrgica. Se realizó resección parcial y biopsia de la lesión. Debido a los hallazgos histológicos y la presencia de marcadores positivos para CD1a y CD207, se confirmó el diagnóstico de HCL. Conclusiones: La HCL es una enfermedad poco frecuente y de difícil diagnóstico por su presentación heterogénea. El granuloma eosinofílico y la vértebra plana como hallazgos imagenológicos pueden orientar el diagnóstico, aunque siempre se debe confirmar histológicamente. Background: Langerhans cell histiocytosis (LCH) is a rare disease, more common in the first three years of life. It is characterized by single or multiple osteolytic lesions due to clonal proliferation of cells histologically similar to Langerhans cells; its clinical presentation is heterogeneous. Case report: 7-year-old female patient with 5 days of progressive lower extremity weakness and difficulty to walk. Physical exam findings were consistent with pyramidal syndrome and lower extremities hypoesthesia. Magnetic resonance imaging (MRI) of spine and cranial computed tomography (CT) were performed. Intracranial pathology was ruled out. The MRI findings showed vertebra plana with epidural and paravertebral involvement, so treatment with steroids and surgical decompression initiated. Partial resection and biopsy of the lesion was performed. Due to histological findings and positive CD1a and CD207 markers, diagnosis of LCH was confirmed. Conclusions: LCH is an uncommon disease with a challenging diagnosis due to its heterogeneous clinical presentation. Eosinophilic granuloma and vertebra plana as imaging findings may guide the diagnosis. However, it should always be confirmed with histological evidence.

Pneumothorax in Patients with Pulmonary Langerhans Cell Histiocytosis.

INTRODUCTION: Pneumothorax often develops in pulmonary Langerhans cell histiocytosis (PLCH), but some patients take a long time to be correctly diagnosed. OBJECTIVES: This study assessed the frequency of pneumothorax in PLCH and analysed the role of chest computed tomography (CT) in the prompt diagnosis. PATIENTS AND MATERIAL: Of the 90 patients with PLCH seen from 2000 to 2015, 29 (32%) had pneumothorax as the initial finding. In this group, 18 (62%) patients were diagnosed within 1 month, whereas the diagnosis was delayed for 4-120 months in 11 (38%) patients. RESULTS: Patients who had pneumothorax as the initial sign of PLCH tended to be younger (mean age 27.7 ± 7.92 vs. 39.9 ± 13.21 years; P = 0.0001), male (69% vs. 43%; P = 0.028), smoked less (mean pack/years 8.4 ± 6.85 vs. 19 ± 17.16; P = 0.003), and had a significantly lower mean FVC (77.96 ± 19.62 vs. 89.47 ± 21.86% pred.; P = 0.015) and FEV1 (68.6 ± 19.93 vs. 79.4 ± 21.48% pred.; P = 0.03 than patients who had no pneumothorax. Recurrent pneumothorax was diagnosed more frequently in the group with a delayed diagnosis (82% vs. 39%; P = 0.02). CT was performed in all of the patients who were diagnosed promptly, but in none of the patients with a delayed diagnosis. CONCLUSIONS: Patients who had pneumothorax as the initial sign of PLCH were younger, more frequently men, and had greater respiratory impairment than those who had no pneumothorax. CT in patients with pneumothorax led to a correct diagnosis of this disease.

Rituximab therapy for patients with Langerhans cell histiocytosis-associated neurologic dysfunction.

OBJECTIVE: Since patients with langerhans cell histiocytosis and neurologic dysfunction (LCH-ND) often have incomplete treatment responses we sought a new treatment regimen. Because of clinical benefit from rituximab in multiple sclerosis patients with neurodegeneration, we evaluated its use in patients with LCH-ND. PARTICIPANTS: Eight LCH-ND patients who had failed prior therapies. METHODS: Charts of the 8 patients treated with rituximab were reviewed. Signs/symptoms and MRI responses were assessed. RESULTS: Seven of eight patients experienced some clinical improvement: gait abnormalities and tremors in four children, proprioceptive deficits in 2, and dysarthria/dysphagia in 2. Five of eight patients demonstrated improvement in intellectual/behavioral/psychological symptoms. CONCLUSION: These findings suggest that prospective studies are warranted to define safety and efficacy of rituximab for patients with LCH-ND.

Lung Function in Pregnancy in Langerhans Cell Histiocytosis.

Pulmonary Langerhans cell histiocytosis (LCH) is a rare disease, affecting usually young people. The course of the disease is variable. In some pulmonary LCH patients a severe lung destruction and progression in spite of chemotherapy is observed, but in others just a cessation of smoking induces a regression of the disease. In the present study we seek to determine the influence of pregnancy on pulmonary function in LCH patients, an unchartered area of research. We addressed the issue by investigating eight pregnant women out of the 45 women hospitalized with the diagnosis of pulmonary LCH in the period from 2000 to 2015. For five of the eight pregnant women it was the second gestation. The median follow-up period was 120 months (range 72-175 months). Ten healthy children were born by a C-section. Two spontaneous miscarriages in the seventh week of gestation, and one tubal ectopic pregnancy were recorded. We found that pregnancy did not significantly influence pulmonary function assessed by the following indices: forced expiratory volume in 1 s (FEV1), lung vital capacity (VC), total lung capacity (TLC), residual volume (RV), diffusing capacity of the lungs for carbon monoxide (DLCO), and the distance and arterial oxygen saturation in 6-min walk test. Only one patient in the third trimester of pregnancy experienced bilateral pneumothorax, with persistent air leak. In all patients, delivery and postpartum period were uneventful. We conclude that pregnancy in pulmonary LCH patients is safe and not associated with deterioration of pulmonary function or blood oxygenation.

How I manage pulmonary Langerhans cell histiocytosis.

Pulmonary Langerhans cell histiocytosis (PLCH) is a rare sporadic cystic lung disease of unknown aetiology that is characterised by the infiltration and destruction of the wall of distal bronchioles by CD1a+ Langerhans-like cells. In adults, PLCH is frequently isolated and affects young smokers of both sexes. Recent multicentre studies have led to the more standardised management of patients in clinical practice. Smoking cessation is essential and is occasionally the only suitable intervention. Serial lung function testing is important because a significant proportion of patients may experience an early decline in forced expiratory volume in 1 s and develop airflow obstruction. Cladribine was reported to dramatically improve progressive PLCH in some patients. Its efficacy and tolerance are currently being evaluated. Patients who complain of unexplained dyspnoea with decreased diffusing capacity of the lung for carbon monoxide should be screened for pulmonary hypertension by Doppler echocardiography, which must be confirmed by right heart catheterisation. Lung transplantation is a therapeutic option for patients with advanced PLCH.The identification of the BRAFV600E mutation in approximately half of Langerhans cell histiocytosis lesions, including PLCH, and other mutations of the mitogen-activated protein kinase (MAPK) pathway in a subset of lesions has led to targeted treatments (BRAF and MEK (MAPK kinase) inhibitors). These treatments need to be rigorously evaluated because of their potentially severe side-effects.